Heterocoagulation of alumina and quartz studied by zeta potential distribution and particle size distribution measurements

Abstract

This paper presents a new approach to characterizing heterocoagulation (i.e. coagulation of mixtures of dissimilar particles) by measuring the zeta potential distribution and the particle size distribution of individual and combined alumina and quartz at pHs 5, 7, and 10. The results show that the heterocoagulation of alumina and quartz would occur at pHs 5 and 7 but not at pH 10. For the alumina and quartz particles under study, the aggregate size was mainly between 1.3 and 8.7 μm and the quartz would act as the core particle and the alumina as the surrounding particles in the heterocoagulation process. The heterocoagulation and dispersion at different pHs and the aggregate structure at pHs 5 and 7 were verified by the scanning electron microscope analysis. The heterocoagulation and dispersion of alumina and quartz at different pHs can be accounted for by the interparticle force revealed by force analysis in the framework of the Deyaguin-Landau-Verwey-Overbeek theory.

Study of arsenic (V) removal of water by using agglomerated alumina

“…2. The zeta potential of agglomerate A-2 steadily decreased from 30 to −25 mV, and the point of zero charge (pzc) was around 8.1, which are close to those values reported in the literature (e.g., 8.0, 8.5-9.3) (Liang et al, 2017;Jiemin et al, 2014;Zamorategui et al, 2016), with the relative difference being smaller than 10%. The stability of the suspensions of the agglomerated adsorbents studied by means of zeta potential at different pH is shown in Fig.…”

Role of magnesium-bearing silicates in the flotation of pyrite in the presence of serpentine slimes

“…As shown inFig. 4, the PZCs of pyro xene, quart z and olivine are at the pH values of 3.2, 2.1 and 2.9, respectively, which are also consistent with the results reported in literatures[25][26][27][28]. Flotation of sulphide ores is normally perfo rmed at neutral or weak alkaline conditions[3].…”

Influence of core‐shell structure on the cure depth in photopolymerizable alumina dispersion

“…For this reason, the zeta potentials for various powders can vary significantly. Figure 3 shows the zeta potential profiles of alumina and quartz versus pH reported elsewhere 18,19 (A) and plots of the zeta potentials of pure α-Al 2 O 3 powder, pure silica powder, mixture of alumina, and silica powders and α-Al 2 O 3 /SiO 2 powder versus pH value obtained in present work (B). In the present research, as the pH was increasing from 2 to 11.3, the zeta potential of alumina was decreasing from 38.6 to −31.3 mV and the isoelectric point (IEP) for alumina was around 9.3, which is close to results of IEP reported by others.…”